num = int(input())
if num >= 30:
  print('Yes')
else:
  print('No') num = int(input()) num int(input()) int input() input if num >= 30:
  print('Yes')
else:
  print('No') num >= 30 num 30 print('Yes') print 'Yes' print('No') print 'No' num = int(input()) int(input()) num
num = int(input())
if num >= 30:
  print('Yes')
else:
  print('No')